Wound retraction apparatus and method

ABSTRACT

A surgical wound retractor is adapted to dilate a wound stretchable to a desired diameter, the retractor includes a first ring having a diameter greater than that desired for the wound and being adapted for disposition interiorly of the wound. A second ring has a diameter greater than that desired for the wound and is adapted for disposition exteriorly of the wound. A plurality of retraction elements are disposed in a generally cylindrical relationship to each other, between the first ring and the second ring. These elements extend through the wound to exert a radial retraction force on the wound which is dependent on the distance separating the first ring and the second ring. Retraction elements, both distensible and non-distensible are contemplated with appropriate attachment elements at the rings to provide for variations in the retraction force. With a suitable retraction sleeve, a third ring can be provided to form a circumferential retainer to vary the retraction force. Rings can also be made inflatable or self-expanding to vary the retraction force. An associated method includes the step of rolling the second ring circumferentially of the third ring to form the circumferential retainer.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a non-provisional application claiming the priority of PCTapplication Ser. No. PCT/US01/50742, filed on Oct. 20, 2000, andentitled “Wound Retraction Apparatus and Method,” which is fullyincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention-relates generally to wound retraction and morespecifically to wound retraction in a laparoscopic surgical procedure.

2. Discussion of the Related Art

During laparoscopic surgery, it is desirable to inflate the abdominalcavity in order to increase the volume of the working space. This isaccomplished with an insufflation gas which must be maintained at apressure sufficient to inflate the abdomen. Maintaining the pressure ofthe insufflation gas is difficult when it is also desirable to insertinstrumentation through the abdominal wall. If the surgeon is interestedin inserting his or her hand in a hand-assisted laparoscopic procedure,the maintenance of insufflation pressure is even more difficult.Currently, several devices exist that accomplish this surgical needalthough they suffer from drawbacks such as difficult placement andcumbersome use. Thus, it is desirable that the wound be retracted,protected, and fixed while maintaining an insufflation seal.

SUMMARY OF THE INVENTION

Wound retraction in accordance with the present invention allows thesurgeon to easily locate a retractor and to provide a solid base for aninstrument or hand seal. This retractor removes the tissue pressure fromthe wrist during hand-assisted laparoscopic surgery. It can also protectthe tissue at the wound site, for example, from abrasion, bacteria orother contaminants organs, such as donor kidneys to be removed withminimal risk or damage. The retractor also opens the wound providinggreater access to the operative site for instruments, such as the handof the surgeon.

In one aspect of the invention, a surgical wound retractor is adapted todilate a wound stretchable to a desired diameter. The retractor includesa first ring having a diameter greater than the desired diameter andbeing adapted for disposition interiorly of the wound. A second ringhaving a diameter greater than the desired diameter of the wound isadapted for disposition exteriorly of the wound. A plurality ofretraction elements are disposed in a generally cylindrical relationshipto each other, between the first ring and the second ring. Theretraction elements are adapted for disposition through the wound toexert a radial retraction force on the wound, the retraction force beingdependent on the distance separating the first ring and the second ring.

In another aspect of the invention, the surgical wound retractorconcludes a plurality of retraction elements each having a distal endand a proximal end, the distal end being coupled to the first ring. Theretraction elements have a plurality of engagement sites disposedbetween the proximal end and the distal end, each of the engagementsites being associated with a different retraction force. The secondring has properties for engaging a selected one of the engagement sitesto provide the desired radial retraction force. The engagement sites mayinclude a plurality of ladder rungs, detents or enlargements, eachassociated with a different retraction force.

The wound retractor may include a retraction sleeve with a first endcoupled to the first ring and a second end coupled to the second ring. Athird ring carried by the sleeve between the first end and the secondend is adapted for disposition exteriorly of the wound. The second ringand the third ring are provided with elastomeric properties facilitatingcircumferential rolling of the second ring relative to the third ring toprovide the sleeve with a radial retraction force sufficient to stretchthe wound to the desired diameter.

In a further aspect of the invention, the third ring is disposedcircumferentially of the sleeve and moveable between a plurality ofpositions between the first ring and the second ring. Each of thepositions is associated with a different radial retraction force. Theretractor includes means for retaining the third ring at one of theplurality of positions to provide the desired radial retraction forceassociated with that position. This retention means may include a fourthring adapted to fix the sheath between the third ring and the fourthring at the desired position. The retention means may also include aclip providing the sheath and the third ring with a fixed relationship.A plurality of circumferential tubes may be included in the retentionmeans, each of the tubes having a fixed relationship with the sheath atone of the desired positions. The tubes are sized and configured toreceive alternatively the third ring at the associated position. Angulartracks can be included in the retention means with the ring configuredto mount relative to one of the tracks at the associated position.

In a further aspect of the invention, a method for operating thesurgical wound retractor includes the step of providing a retractionsleeve having an axis, a first end attached to a first ring and a secondend attached to a second ring axially spaced from the first ring. Athird ring is provided in a generally fixed relationship to the sleevebetween the first ring and the second ring. Then the second ring andthird ring are circumferentially rolled to form a circumferentialretainer positioned axially of the first ring at a particular distanceassociated with the desired radial retraction force on the wound. In therolling step, the third ring can be rolled outwardly of the second ringto form the circumferential retainer. The second ring can then be rolledoutwardly of the third ring to move the circumferential retainer to theparticular distance.

These and other features and advantageous of the invention will becomemore apparent with a description of preferred embodiments and referenceto the associated drawings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the present invention:

FIG. 2 is a perspective axial cross section view of the embodimentillustrated in FIG. 1;

FIG. 3 is a perspective view of an additional embodiment of theinvention including multiple retraction elements;

FIG. 4 is a perspective view of an additional embodiment of theinvention including an elastomeric sleeve and multiple retentionelements secured onto hook features;

FIG. 5 having a sheath attached to an outer ring with clamps;

FIG. 6 is a perspective view of a further embodiment of the inventionincluding multiple ladders with rungs providing a sheath with desiredtension;

FIG. 7A is a perspective view of a further embodiment of the inventionincluding retention elements in the form of zip ties with detents;

FIG. 7B is an enlarged perspective view of a detent adapted for use inthe embodiment of FIG. 7A;

FIG. 8A is a perspective view of an additional embodiment of theinvention wherein the retention elements include a series of ropes withenlargements or knots operable relative to a window in the outer ring;

FIG. 8B is an enlarged perspective view of a window configurationadapted for use with the embodiment of FIG. 8A;

FIG. 9 is an axial cross section view of a further embodiment of theinvention including a threaded second ring and a threaded third ringoperable with a sealing cap:

FIG. 10 is an axial perspective view of a further embodiment including amoveable third ring;

FIG. 11A is an axial schematic view showing the FIG. 10 embodiment in anatural state;

FIG. 11B is an axial schematic view showing the FIG. 10 embodiment in aretraction state;

FIG. 12-FIG. 15 are axial perspective views showing steps in a preferredmethod for operating the FIG. 10 embodiment;

FIG. 12 is an axial perspective view showing the second ring beingrolled over the third ring to create a circumferential retainer;

FIG. 13 is an axial perspective view showing the third ring being rolledover the second ring to move the circumferential retainer to a desiredposition;

FIG. 14 is an axial view showing the step of FIG. 12 with the retractoroperatively disposed;

FIG. 15 is an axial cross section view of the step illustrated in FIG.13 showing the retractor operatively disposed;

FIG. 16 is an axial perspective view of a further embodiment including aclip for retaining the third ring at a desired position between thesecond ring and the first ring;

FIG. 17 is an axial perspective view showing multiple loops eachdisposed at a particular distance from the first ring and adapted toalternatively receive the third ring at a desired distance from thefirst ring;

FIG. 18 is an axial perspective view of an embodiment including tracksand a third ring with a mating groove;

FIG. 19 is an axial perspective view of an embodiment including a fourthring for clamping the sheath between the third ring and the fourth ring;

FIG. 20 is an axial perspective view of a further embodiment including aseries of third rings for forming the retention roll at differentpositions between the first and second rings;

FIG. 21 is an axial perspective view of an embodiment includingunidirectional interlocking rings in a separated state;

FIG. 22 is an axial perspective view of the unidirectional interlockingrings in a proximate clamping state;

FIG. 23A is a cross sectional view showing a unidirectional mechanismwith a third ring, fourth ring, and associated cap ring including awedge;

FIG. 23B shows the rings of FIG. 23A operatively disposed to wedge thesheath between the second and fourth rings;

FIG. 24 is an axial cross section view showing an embodiment of aunidirectional retention member, including a one-way roller;

FIG. 25 is an axial cross section view showing a unidirectionalretention member in the form of a ratchet;

FIG. 26 is an axial cross section view of a further embodiment whereinthe third ring is expandable to adjust the distance between the thirdring and the first ring:

FIG. 27 is an axial cross section view showing the embodiment FIG. 26with the third ring including foam in an expanded state;

FIG. 28 is an axial cross section view of an embodiment showing a secondring being rolled into an inverted retention ring:

FIG. 29 is an axial cross section view showing the FIG. 28 embodimentwith the rolled ring held by the retainer; and

FIG. 30 is an axial cross section view illustrating an embodiment withtwo end rings and at least one intermediate ring.

DESCRIPTION OF PREFERRED EMBODIMENTS AND BEST MODE OF THE INVENTION

The basic concept of retracting and protecting a wound site isillustrated in the prospective view of FIG. 1 wherein a wound 10 isformed in an abdominal wall 11. In this embodiment, a retractor 12 usestwo rings 14 and 16 which are fixed to an elastic sheath 18. The sheath18 has a generally cylindrical configuration and is disposed along anaxis 21. The rings 14 and 16 are disposed in respective planes whichextend radially of the axis 21.

The sheath 18 has elastomeric properties, but in its natural,unstretched state the two rings 14 and 16 are separate by a naturaldistance. The lower ring 14 is placed interiorly of the abdominal wall11 and the upper ring 14 is stretched beyond the natural distance awayfrom the lower ring. Once the elastic sheath 18 has been stretched to adistance greater than the abdominal wall thickness, the upper ring 16 isplaced on the surface of the skin.

Since the diameters of the rings 14, 16 are greater than that desiredfor the wound site 10, they will have sufficient footing to maintainthis tension between the two rings 14, 16. This tension is created bythe elastic material that has been stretched and retained at a distancegreater than the natural distance. It will be appreciated that in manyembodiments, the sheath 18 can be formed of a non-elastic sheathingmaterial. In a similar manner, the rings 14 and 16 may be provided witha rigid configuration or alternatively may be formed of an elastromericmaterial.

FIG. 2 shows a simple schematic of the ring dynamics illustrated in FIG.1, with the retractor 12 operatively disposed across the abdominal wall11. The elastic sheet sheath 18 acts as a circumferential spring 23around the wound site 10 that evenly distributes the tension between thetwo rings 14 and 16, as represented by arrows 25 & 27. In addition, theelastic sheeting provides a radial retraction force 30 around the woundto enlarge the wound site 10 in order to facilitate the passage ofinstruments, such as the hand of the surgeon.

The amount of tension force between the two rings 14 and 16 can becontrolled by the elastomeric proportion of the elastic sheath 18. Inorder to accommodate a larger range of abdominal wall thicknesses, amaterial with a higher elasticity can be chosen to allow for greaterstretch.

FIG. 3 illustrates the “sandwiching” of the abdominal wall between thetwo rings 14, 16 using elastic tensioners, such as rubber bands 36. Theuse of elastic tensioners allows for a greater range of wall thicknessesbecause the tensions can be selected at the time of application. Forinstance, the user would make an incision and measure the actualabdominal wall thickness. He would then choose the appropriate rubberbands providing the desired tensions for the given application. In thiscase the rubber bands 36 could be secured by hooks 38 provided on one orboth of the rings 14 and 16. This gives the user more versatility withthe device.

FIG. 4 is a different embodiment which provides even furtherversatility. This design is not limited by the fixed distance betweenthe rings 14, 16 of the retractor 12. Instead, the inner ring 14 will befixed to the sheath 18, and the upper ring 16 will comprise a separateassembly. Initially, the inner ring 14 is placed into the peritoneumcavity. Then the elastic material is pulled taut and secured onto hookfeatures 41 located on the outer ring 16. This allows the user to fixthe retractor 12 to an abdominal wall of any size.

FIG. 5 shows an additional embodiment wherein the sheath 18 is attachedto the outer ring 16 using clamps 43. FIG. 6 illustrates anotherembodiment wherein the sheath 18 is attached to the outer ring 16 usingladders 45 with rings 46, that may be connected to the external surfaceof the sheath 18. Once the preferred tension of the sheath 18 has beenattained, the user simply hooks an appropriate rung 46 onto anassociated hook 47 located on the outer ring 16.

FIG. 7A shows a structure which sandwiches the abdominal wall 11 betweenthe two rings 14,16 using zip ties 50. After the inner ring 14 has beenplaced, the ties 50 can be pulled tight through associated holes 54 tofix the rings 14, 16 relative to the abdominal wall 11. As illustratedin FIG. 7B, the zip ties 50 may be formed with a plurality of grooves 52which extend traverse or perpendicular to the length of the tie 50. Inoperation, the tie 50 is threaded through the hole 54 in the upper ring16 where one of the grooves 52 is engaged by a tongue 56 which preventsmovement of the tie 50 back through the hole 54.

FIG. 8A shows a method of sandwiching the abdominal wall between the tworings 14, 16 using a series of ropes 58, each having a plurality ofknots 61. After the ring 14 has been placed, the ropes 52 can betensioned and one of the knots 61 secured into an associated holderlocated on the outer ring 16. In this embodiment, each rope 58 is drawnupwardly through an associated window 63 in the outer ring 16. Thiswindow 63 will typically be provided with portion 65 larger than theknots 61, and portion 67 smaller than the knots 61 as illustrated inFIG. 8B.

An additional embodiment of the wound retractor 12 is illustrated inFIG. 9 where elements of structure similar to those previously describedare designated by the same reference numeral followed by the lower caseletter “a.”

This embodiment is adapted for opening the wound 10 in the abdominalwall 11 and for maintaining the wound 10 in the open configuration toallow access into the abdominal cavity. The device includes the sheath28 a which lines the wound 10 to prevent or limit the risk of portsitemetastasis, and the outer ring 16 a. The outer ring 16 a also includes asealing surface 72 at its base which is designed to seal against theexterior surface of the abdominal wall 11. The device further comprisesthe thin film sheath 28 a with a ring 74, having external threads 76,which is attached to the proximal end of the sheath 28 a, and with theinner ring 14 a attached to the distal end of the sheath 28 a. The innerring 14 a is designed to be placed inside the wound 10 while the rings16 a and 74 remain external to the wound 10.

Once the inner ring 14 a is placed inside the wound 10 and into theperitoneal cavity, the outer ring 16 a can be rotated clockwise relativeto the inner ring 14 a. As the internal thread 70 on the outer ring 16 aengage the external threads 76 on the ring 74, the ring 74 is drawnproximally stretching the sheath 28 a. This opens the wound 10 and drawsboth the outer ring 16 a and the inner ring 14 a toward the abdominalwall 11. A primary seal is created between the inner ring 14 a and theabdominal wall 11, while a secondary seal is formed between the surface72 of the outer ring 16 a and the exterior surface of the abdominal wall11. A sealing cap 81 can then be attached to the proximal end of theouter ring 16 a to permit insufflation and otherwise facilitate alaparoscopic procedure. The sealing cap 81 can be removed at any time toallow conversion from laparoscopic surgery to open surgery.

Perhaps the most significant advantage associated with this embodimentis that the device enables a surgeon to retract and protectively line anabdominal wall incision, while being able to easily adjust the retractor12 a to accommodate variations from patient to patient in the thicknessof the abdominal wall 11. The device effectively seals around theinterior and 20 exterior of the wound 10, which allows the sealing cap81 to be attached to seal the abdominal cavity and enable a laparoscopicprocedure to be performed.

Another embodiment of the retractor 12 is illustrated in FIGS. 10-14where elements of structure similar to those previously discussed aredesignated with the same reference numeral followed by the lower caseletter “b.” In this embodiment, the retractor 12 b includes the thinfilm sheath 28 b which lines the wound to prevent or limit the risk ofportsite metastasis. The inner and outer rings, 14 b and 16 b,respectively, are attached to opposing ends of the sheath 28 b in themanner previously described. However, in this embodiment, a third ring83 is fixed to the sheath 28 b between the rings 14 b and 16 b.

In order to achieve the desired retraction, the inner ring 14 b ispositioned interiorly of the abdominal wall 11 as illustrated in FIG.11A. Then the sheath 28 b is pulled outwardly through the wound 10,tensioning the sheath 28 b and causing the abdominal wall 11 to retractor open as illustrated in FIG. 11B.

At this point, it is desirable to maintain the retraction by preventingthe sheath 28 b from pulling back into the wound 10. This maintenance oftension on the sheath 28 b is addressed in a unique manner with theembodiment of FIG. 10 wherein the rings 16 b and 83 are preferablyprovided with elastromeric characteristics.

In the manner illustrated in FIG. 12, the ring 16 b can be moveddistally over the ring 83. This creates a circumferential retainer orring bundle 85 which is illustrated in the perspective view of FIG. 13.In this process, the ring 16 b is stretched circumferentially outwardlyof the ring 83 to form the bundle 85. This formation is furtherillustrated in the cross section schematic view of FIG. 14 where thebundle 85 of elastomeric rings presses against the outer surface of theabdominal wall 11 to maintain tension on the sleeve 28 b. With referenceto FIG. 15, it will be appreciated that the ring bundle 85 can befurther rotated to move the third ring 83 outwardly and distally of thering 16 b as required to produce and maintain the desired tension on thesheath 28 b.

With the embodiment of FIG. 10, retraction is achieved by positioningthe ring 83 above the ring 16 b, and pulling the sheath 28 b upwardlyfrom the wound 10 (FIG. 12). The sheath is prevented from pulling backinto the incision by stretching the ring 83 out, around, and under thering 16 b.

The degree of retraction or how much the sheath is pulled upwardly, isdepended on the height of the ring 83 about the abdominal wall 11. Thisheight can be adjusted in the embodiment of FIG. 16 wherein elements ofstructure similar to those previously described are designated with thesame reference numeral followed by the lower case letter “c.” In thisembodiment, the ring 83 c can be disconnected from and moved relative tothe sheath 28 c. At a desired location above the inner ring 14 c, thering 83 c can be fixed to the sheath 28 c, for example by a clip 87.

Clamps or clips may be used to lock the movable ring at the appropriateheight as shown in FIG. 16. Also, a series of open loops 88 (FIG. 17) ortracks 89 (FIG. 18) can be fixed to the sheath 28 c at differentdistances from the inner ring 14 c to hold the ring 83 c at differentheights.

Alternatively, as illustrated in FIG. 19, the moveable ring 83 can beformed as two complimentary rings. The outer ring 16 b can be disposedoutwardly of the sheath 28 c and a fourth ring 90 can be disposedinwardly of the sheath 28 c. These two rings 14 c and 90 function toclamp the sheath 28 c so that the ring 83 c is maintained in a fixedposition by the complimentary locking ring 90.

The inner locking rings 83 c and 90 of the FIG. 19 embodiment providefor simple operation of the retractor 12. These interlocking rings 83and 90 can be pushed down so that they rest on the outer surface of theabdominal wall 11. As the sheath 28 c is drawn upwardly to achieve theproper degree of tension, it is easily moved between the rings 83 c and90. However, any tendency of this sheath 28 c to move back into thewound site merely tightens the interlocking relationship of the rings 83c and 90. Thus, the desired degree of tension is maintained on thesheath 28 c until it is again pulled to release the locking ring 90 fromthe ring 83 c.

In still a further embodiment, illustrated in FIG. 20, severalintermediate rings. 92, 94, 96 and 98 can be provided between the innerring 14 c and the outer ring 16 c. With this embodiment, the rings, suchas the ring 16 c, 92 and 94, disposed outwardly of the abdominal wall 11can be rolled into the ring bundle 85 c to maintain the desired tensionon the sheath 28 c. In this case, the rings 96 and 98, which are notincluded in the ring bundle 85 c, contact the abdominal wall 11 toprovide increased friction and perhaps increased retraction at the woundsite.

A further advantage of these embodiments is that they enable the surgeonto retract and protectively cover the wound 10 while permittingadjustment of the retractor 12 c to variations in thickness of theabdominal wall 11. These devices provide an airtight seal around thewound 10, thus allowing an airtight cap or access port to be attached toenable laparoscopic surgery. Furthermore, usage of these devices issimple in that retraction can be achieved with one motion by graspingthe proximal ring 16 c and pulling it up from the wound 10 and thenmerely releasing it.

The one-way characteristics of the interlocking rings 83 c and 90 areillustrated in the progressive views of FIGS. 21 and 22. With referenceto these figures, it can be seen that retraction is maintained bypreventing the sheath 28 c from pulling back into the wound 10 by meansof the one-way operation of the interlocking rings 83 c and 90. Thesheath 28 c slides easily through the interlocking rings 83 c and 90 inthe upper direction, but is prevented from sliding through the rings 83c and 90 in the downward direction. In order to disengage or separatethe interlocking rings 83 c and 90, one need only re-tension the sheath28 c by pulling it proximally thereby unlocking the rings 83 c and 90.This enables the ring 83 c to be removed from the sheath 28 c in orderto remove the retractor 12 from the wound site.

Other one-way mechanisms can be formed, for example, with a wedge 93 asillustrated in FIGS. 23A and 23B, a one-way roller 95 as illustrated inFIG. 24, or a one-way ratchet 97 as illustrated in FIG. 25. Bumps,over-braid, threads or coatings on the sheath 28 can be added foradditional traction using these one-way mechanisms. Alternatively,features such as indentations or protrusions on the sheath 28 can permitit to pass in only one direction.

A further embodiment of the wound retractor 12 is illustrated in FIGS.26 and 27 wherein elements of structure are similar to those previouslydescribed or designated with the same reference numeral followed by thelower case letter “d.” These embodiments include an expandable foamannulus 101 which is disposed in a compartment 103 sealed by a valve104. This compartment 103 is formed between the rings 14 d and 16 d, andproximate the outer ring 16 d. In this location, the compartment 103 isoperatively disposed exteriorly of the abdominal wall 11. As in any ofthe embodiments previously disclosed, a sealing cap 105 can be disposedover the outer ring 16 d to facilitate laparoscopic surgery. After theretractor 12 d is operatively disposed as illustrated in FIG. 27. Thevalve 104 can be opened to permit air into the cavity 103. This alsopermits the foam annulus 101 to expand as illustrated in FIG. 27 therebyelevating the ring 16 d above the abdominal wall 11 and tensioning thesheath 28 d.

As the annular foam 101 expands to a high profile state, seals areformed on both sides of the wall 11 around the sheath 28 d. In addition,the wall 11 is retracted from the wound 10. To remove the woundretractor 12 from the patient, the surgeon simply opens the valve 104and pulls the inner ring 14 d out through the wound 10. While anexpandable foam is described for this embodiment, additional materialscould be utilized which expand upon contact with the inlet air.

One advantage associated with this embodiment is that the device enablesa surgeon to quickly retract and protectively line an abdominal wallincision while being able to easily accommodate variations from patientto patient in the thickness of the abdominal wall. In addition. Thedevice effectively seals around the interior and exterior of theincision, and allows a sealing cap to be attached to seal the abdominalcavity and to enable a laparoscopic procedure to be performed.

A wound retractor with an inverting ring 107 is illustrated in FIGS. 28and 29 where elements of structure similar to those previously disclosedare designated with the same reference numeral followed by the lowercase letter “e.” The device includes the sheath 28 e which lines thewound 10 to prevent or limit the risk of portsite metastasis. The deviceincludes base 110 with a sealing ring 14 on its distal end, which isdesigned to seal against the exterior abdominal wall 11 of the patient.The device includes a thin film sheath 28 e with the inverting ring 107configured to lock into the base 110 which is attached to the proximalend of the sheath 28.

The sealing ring 14 e is designed to be placed inside the incision whilethe external inverting ring 107 remains external to the incision. Thebase 110 is configured to move freely between the rings 14 e and 107.Once the ring 14 e is placed inside the incision and into the peritonealcavity, the external ring 107 is continuously rolled or inverted, whichdraws the incision open and also draws both the external ring 107 andthe peritoneal ring 14 e toward the abdominal wall. Once all of theslack in the sheath 28 e has been taken up by rolling or inverting theexternal ring 107, the external ring can then be pushed into a recess114 in the base 110 which is configured to lock the ring in position andthereby maintain the tension on the sheath 28 e. With the proper amountof tension placed upon the sheath 28 e, a primary seal is createdbetween the peritoneal ring 14 e and the anterior abdominal wall, and asecondary seal is created between the sealing ring 112 of the base 110and the exterior abdominal wall. A sealing cap 116 can then be attachedto the proximal end of the base and the patient can be insufflated withcarbon dioxide to allow a laparoscopic procedure such as a gastricbypass to be performed. The sealing cap can be removed at any time toallow conversion from laparoscopic surgery to open surgery.

A most significant advantage associated with this embodiment is that thedevice enables a surgeon to retract and protectively line an abdominalwall incision while being able to easily adjust the device toaccommodate variations from patient to patient in the thickness of theabdominal wall. The device effectively seals around the interior andexterior of the incision, which allows a sealing cap to be attached toseal the abdominal cavity ad enable laparoscopic procedure to beperformed.

A further embodiment of the wound retractor is, illustrated in FIG. 30,where elements of structure similar to those previously disclosed aredesignated with the same reference numeral followed by the lower caseletter “f.” This embodiment includes three separate rings 16 f, 14 f,and 83 f. The device has a tubular sheath 28 f which lines the incisionto prevent or limit the risk of portsite metastasis. The device includesthe external ring 16 f attached to the proximal end of the sheath 28 f,the intermediate ring 83 f attached to the center of the sheath, and aperitoneal ring attached to the distal end of the sheath 28 f. Theperitoneal ring is designed to be placed inside the incision while theeternal ring 16 f remains external to the incision. The intermediatering 83 f may remain external to the incision or may lie within theincision itself depending upon how the three rings are oriented.

This wound retractor has four different fixed lengths to accommodateabdominal walls of four different thicknesses. The first length, whichis the longest, is achieved by simply placing the peritoneal ring 14 finto the incision. The tension of the sheath between the external ring16 f and the peritoneal ring 14 f maintains the incision in an openconfiguration. If the thickness of the abdominal wall 11 is less thanthe distance between the eternal ring 16 f and the peritoneal ring 14 f,then a shorter length can be selected.

The second length., which is less than the first length, is achieved bysimply placing the peritoneal ring 14 f into the incision, and thenpulling the sheath 28 f upwards until the intermediate ring 83 f isexternal to the incision. The tension of the sheath 28 f between theintermediate ring 83 f and the peritoneal ring 14 f maintains theincision in an open configuration. If the thickness of the abdominalwall 11 is less than the distance between the intermediate rind 83 f andthe peritoneal ring 14 f then a shorter length can be selected.

The third length, which is less than the second length, is achieved byinserting the peritoneal ring 14 f into the incision and then pullingthe intermediate ring 83 f over the external ring 16 f. The tension ofthe sheath between the peritoneal ring and the combination of theexternal ring and the intermediate ring maintains the incision in anopen configuration. If the thickness of the abdominal wall is less thanthe third length, then the fourth length will have to be selected.

The fourth length, which is less than the third length, is achieved byfirst pulling the intermediate ring 83 f through the external ring 16 f,and then pulling the intermediate ring 83 f over the external ring 16 f.The tension of the sheath 28 f between the peritoneal ring 14 f and thecombination of the external ring 16 f and the intermediate ring 83 f,maintains the incision in an open configuration. This 3-ring retractorcan therefore be positioned to effect four different lengths toaccommodate variations in the thickness of the abdominal wall frompatient to patient.

A most significant advantage associated with this embodiment is that thedevice enables a surgeon to retract and protectively line an abdominalwall incision while being able to easily adjust the device toaccommodate variations from patient to patient in the thickness of theabdominal wall. The device is also very low in cost since it includesonly four components, 3 rings 14 f, 16 f, and 83 f, and a tubular sheath28 f.

It will be understood that many other modifications can be made to thevarious disclosed embodiments without departing from the spirit andscope of the concept. For example, various sizes of the surgical deviceare contemplated as well as various types of constructions andmaterials. It will also be apparent that many modifications can be madeto the configuration of parts as well as their interaction. For thesereasons, the above description should not be construed as limiting theinvention, but should be interpreted as merely exemplary of preferredembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the present invention as defined by thefollowing claims.

1. A surgical wound retractor adapted to dilate a wound stretchable to adesired diameter, the retractor comprising: a first ring having adiameter greater than the desired diameter of the wound and beingadapted for disposition interiorly of the wound; a second ring having adiameter greater than the desired diameter of the wound and beingadapted for disposition exteriorly of the wound; at least one retractionelement having an outer surface and an inner surface, the retractionelement being disposed in a generally cylindrical form between the firstring and the second ring to exert a radial retraction force on thewound, the retraction force being dependent on a distance separating thefirst ring and the second ring; and at least one retention element beingadapted for disposition through the wound along the inner surface of theretraction element and operably connected between the first ring and thesecond ring to control the distance separating the first ring and thesecond ring.
 2. The surgical wound retractor recited in claim 1, whereinthe at least one retention element includes a plurality of elastomericbands.
 3. The surgical wound retractor recited in claim 2, wherein: atleast one of the first ring and the second ring includes a plurality ofretainers; and each of the elastomeric bands is adapted for retention byan associated one of the retainers on at least one ring.
 4. The surgicalwound retractor recited in claim 3, wherein the retainers comprise aplurality of hooks.
 5. The surgical wound retractor recited in claim 2,wherein the elastomeric bands are selected from a group of elastomericbands each having different elastomeric properties.
 6. A surgical woundretractor adapted to dilate a wound stretchable to a desired diameter,the retractor comprising: a first ring having a diameter greater thanthe desired diameter of the wound and being adapted for dispositioninteriorly of the wound; a second ring having a diameter greater thanthe desired diameter of the wound and being adapted for dispositionexteriorly of the wound; a retraction element having an outer surfaceand an inner surface, the retraction element being disposed in agenerally cylindrical form between the first ring and the second ring toexert a radial retraction force on the wound, the retraction force beingdependent on a distance separating the first ring and the second ring;at least one retention element having a distal end and a proximal end,and being coupled to the first ring at the distal end along the innersurface of the retraction element to control the distance separating thefirst ring and the second ring; the retention element having a pluralityof engagement sites disposed between the proximal end and the distalend, each of the engagement sites being associated with a differentretraction force; and the second ring having properties for engaging aselected one of the engagement sites to provide the associated radialretraction force.
 7. The surgical wound retractor recited in claim 6,wherein the engagement sites of the retraction elements include aplurality of ladder rungs, each associated with a different retractionforce.
 8. The surgical wound retractor recited in claim 6, wherein: theengagement sites include a plurality of grooves each associated with adifferent retraction force; and the second ring includes a lever bias toengage a selected one of the grooves to provide the associatedretraction force.
 9. A surgical wound retractor recited in claim 6,wherein: the engagement sites include a plurality of enlargements eachassociated with a different retraction force; and the second ring hasproperties for engaging a selected one of the enlargements to providethe associated retraction force.
 10. A surgical wound retractor, adaptedto dilate a wound stretchable to a desired diameter, the retractorcomprising: a first ring having a diameter greater than the desireddiameter of the wound and being adapted for disposition interiorly ofthe wound; a second ring adapted for disposition exteriorly of thewound; a retraction sleeve having a generally cylindrical configurationwith a first end coupled to the first ring and a second end coupled tothe second ring; a third ring coupled to the sleeve between the firstend and the second end, the third ring being adapted for dispositionexteriorly of the wound; and the second ring and the third ring havingelastomeric properties facilitating the circumferential rolling of thesecond ring and the third ring relative to one another to provide thesleeve with a radial retraction force sufficient to stretch the wound tothe desired diameter.
 11. The surgical wound retractor recited in claim10, wherein the second ring has elastomeric properties for beingcircumferentially rolled relative to the second ring to provide thedesired retraction force.
 12. The surgical wound retractor recited inclaim 10, wherein the second ring is sized and configured to be rolledcircumferentially of the third ring to form a circumferential retainer.13. The surgical wound retractor recited in claim 10, wherein the secondring is sized and configured to be rolled exteriorly of the third ringto form the circumferential retainer.
 14. The surgical wound retractorrecited in claim 10, wherein the third ring has properties for expandingin size in order to vary the distance between the first ring and thethird ring in the desired retention force.
 15. The surgical woundretractor recited in claim 14, wherein the third ring includesself-expanding foam.
 16. A surgical wound retractor, adapted to dilate awound stretchable to a desired diameter, the retractor comprising: afirst ring having a diameter greater than the desired diameter of thewound and being adapted for disposition interiorly of the wound; asecond ring adapted for disposition exteriorly of the wound; aretraction sleeve having a generally cylindrical configuration with afirst end coupled to the first ring and a second end coupled to thesecond ring; a third ring disposed circumferentially of the sleeve andmoveable between a plurality of positions between the first ring and thesecond ring, each of the positions being associated with a differentradial retraction force; and means for retaining the third ring at oneof the plurality of positions in order to provide the desired radialretraction force associated with that position, wherein the retainingmeans comprises a fourth ring adapted to fix the sheath between thethird ring and the fourth ring at the desired position.
 17. The surgicalwound retractor recited in claim 16, wherein: the second ring isassociated with a first screw thread; the third ring is associated witha second screw thread sized and configured to engage the first screwthread whereby rotation of the second ring relative to the first ringadjusts the position of the third ring relative to the second ring andthe first ring to provide the sheath with the desired radial retractionforce.
 18. The surgical wound retractor recited in claim 16, wherein theretaining means further comprises a wedge disposed between the thirdring and the fourth ring.
 19. The surgical wound retractor recited inclaim 16, wherein the retaining means comprises at least one clipproviding the sheath and the third ring with a fixed relationship at thedesired position.
 20. A surgical wound retractor adapted to dilate awound stretchable to a desired diameter, the retractor comprising: afirst ring having a diameter greater than the desired diameter of thewound and being adapted for disposition interiorly of the wound; asecond ring adapted for disposition exteriorly of the wound; aretraction sleeve having a generally cylindrical configuration with afirst end coupled to the first ring and a second end coupled to thesecond ring; a third ring disposed circumferentially of the sleeve andmoveable between a plurality of positions between the first ring and thesecond ring, each of the positions being associated with a differentradial retraction force; and means for retaining the third ring at oneof the plurality of positions in order to provide the desired radialretraction force associated with that position, wherein the retainingmeans comprises a plurality of circumferential tubes each having a fixedrelationship with the sheath at one of the desired positions, each ofthe tubes being sized and configured to receive alternately the thirdring.
 21. A surgical wound retractor adapted to dilate a woundstretchable to a desired diameter, the retractor comprising: a firstring having a diameter greater than the desired diameter of the woundand being adapted for disposition interiorly of the wound; a second ringadapted for disposition exteriorly of the wound; a retraction sleevehaving a generally cylindrical configuration with a first end coupled tothe first ring and a second end coupled to the second ring; a third ringdisposed circumferentially of the sleeve and moveable between aplurality of positions between the first ring and the second ring, eachof the positions being associated with a different radial retractionforce; and means for retaining the third ring at one of the plurality ofpositions in order to provide the desired radial retraction forceassociated with that position, wherein the retaining means includes aplurality of angular tracks each fixed to the sleeve at an associatedone of the positions; and the ring is sized and configured for mountingrelative to one of the tracks at the associated position.
 22. A methodfor operating a surgical wound retractor to provide a desired radialretraction force on a wound, the method comprising the steps of:providing a retention sleeve having an axis, a first end attached to afirst ring and a second end attached to a second ring axially spacedfrom the first ring; providing a third ring, generally fixed to thesleeve between the first ring and the second ring; rolling the secondring and the third ring outwardly and circumferentially of one anotherto form a circumferential retainer, the retainer being positionedaxially of the first ring at a particular distance associated with thedesired radial retention force on the wound to produce and maintain thedesired radial tension on the retention sleeve.
 23. The method recitedin claim 22, wherein the rolling step further comprises the step of:rolling the second ring circumferentially of the third ring to move thecircumferential retainer to the particular distance associated with thedesired radial retention force.
 24. The method recited in claim 22,wherein: the second providing step includes the step of providing aplurality of third rings each fixed to the sleeve at an associated axialposition between the first ring and the second ring; and the rollingstep includes the steps of creating an imaginary line at the particulardistance from the first ring, the imaginary line being disposed betweenan adjacent pair of the third rings; and rolling with the second ringall of the third rings disposed on the side of the imaginary lineopposite the first ring to form the circumferential retainer at theparticular distance.
 25. A surgical wound retractor, adapted to dilate awound stretchable to a desired diameter, the retractor comprising: afirst ring having a diameter greater than the desired diameter of thewound and being adapted for disposition interiorly of the wound; asecond ring adapted for disposition exteriorly of the wound; aretraction sleeve having a generally cylindrical configuration with afirst end coupled to the first ring and a second end coupled to thesecond ring; a third ring disposed circumferentially of the sleeve andmoveable between a plurality of positions between the first ring and thesecond ring, each of the positions being associated with a differentradial retraction force; and a unidirectional mechanism for retainingthe third ring at one of the plurality of positions in order to providethe desired radial retraction force associated with that position.wherein the unilateral mechanism includes a ratchet assembly.
 26. Asurgical wound retractor adapted to dilate a wound stretchable to adesired diameter, the retractor comprising: a first ring having adiameter greater than the desired diameter of the wound and beingadapted for disposition interiorly of the wound; a second ring adaptedfor disposition exteriorly of the wound; a retraction sleeve having agenerally cylindrical configuration with a first end coupled to thefirst ring and a second end coupled to the second ring; a third ringdisposed circumferentially of the sleeve and moveable between aplurality of positions between the first ring and the second ring, eachof the positions being associated with a different radial retractionforce; and a unidirectional mechanism for retaining the third ring atone of the plurality of positions in order to provide the desired radialretraction force associated with that position, wherein theunidirectional mechanism includes a one-way roller.